SGER: Biogeochemistry of Lipid Biomarkers in Modern and Fossil Bivalve Shells

有机地球化学家广泛使用整体有机质和主要化合物类中的轻稳定同位素分析来评价细粒沉积岩的成因和热成熟度。在过去的五年中，使用与同位素质谱计相连的气相色谱仪的仪器来确定单个有机化合物的碳同位素组成已经成为可能。个别化合物的同位素比率监测(IRM/GC-MS)在广泛的地质问题上的应用已经开始出现。PIS将利用IRM/GC-MS直接比较双壳类贝壳软组织和矿化组织中有机物质之间的脂质生物标记物(有机分子化石)的同位素组成。活贝壳和化石贝壳都将被调查。如果可以从贝壳中提取足够数量的脂类，如果贝壳中的脂类与地幔组织的同位素组成相似，那么将贝壳脂类用于分子古生物学和古生态研究应该是可行的。

Analyses of light stable isotopes in bulk organic matter and major compound classes are widely used by organic geochemists to assess the origin and thermal maturity of fine-grained sedimentary rocks. In the last five years, it has become possible to determine the carbon isotopic composition of individual organic compounds using instruments with a gas chromatograph coupled to an isotope mass spectrometer. Application of isotope ratio monitoring of individual compounds (IRM/GC-MS) to a wide range of geological problems is beginning to emerge. PIs will utilize IRM/GC-MS for a direct comparison of the isotopic composition of lipid biomarkers (organic molecular fossils) between soft tissues and organic matter within mineralized tissues of bivalve shells. Both living shells and fossil shells will be surveyed. If sufficient quantities of lipids can be extracted from shells and if lipids from the shell mimic the isotopic composition of the mantle tissues, then it should be feasible to use shell lipids for studies of molecular paleontology and paleoecology.